Inside the Numbers: The battle for No.1 heads to Cincy

CINCINNATI, Ohio -- The Battle for No.1 heads to the Western & Southern Open this week, where four women -- Simona Halep, Angelique Kerber, Elina Svitolina, and Caroline Wozniacki -- have a chance to overtake World No.1 and defending champion Karolina Pliskova.

Karolina Pliskova is the defending champion at the Western & Southern Open. (Getty)

Here are the point scenarios for the upcoming week in Cincinnati:

A champion in Cincinnati last year, Pliskova is defending 900 ranking points. When factoring the points that will come off on the Monday after Cincinnati, the Czech will hold a narrow 240 point advantage over No.2 Simona Halep.

Pliskova and Halep have been jostling for the No.1 ranking since the French Open, and it was the 25-year-old Czech who got over the line first, overtaking Angelique Kerber after Wimbledon to become the 23rd woman to hold the No.1 ranking.

Either Pliskova or Halep can secure the No.1 ranking with a title run this week. Should they fall short, the door opens for five-time title winner Svitolina, reigning US Open champion Kerber, and six-time finalist Wozniacki.

Svitolina finds herself in contention for the No.1 ranking after becoming the first woman to ever win three Premier 5 titles in a single season, beating Wozniacki for a second time in a Premier 5 final this year to win the Rogers Cup.

The 22-year-old, who will rise to No.4 on Monday and No.1 in the Porsche Race to Singapore Leaderboard, would need to make the final in Cincinnati to have a chance at the No.1 ranking.

She would also need Pliskova to lose in her opening round, Halep to lose before the semifinals, and Wozniacki to not win the title.

Wozniacki is bidding to return to No.1 for the first time since 2012. She would need to snap her 0-6 record in finals this year and win the title to have a chance at No.1.

Along with the title, the Dane would also need Pliskova to lose in her opening round and Halep to lose before the semifinals.

The toughest road to a No.1 return belongs to Kerber, who would need to win the title with Pliskova losing in her opening round, Halep losing before the semifinals, and Svitolina lose before the final.

Cincinnati is the tournament that started it all for Pliskova, who built on her title run to make her first major final at the US Open. Can she make another deep run and fend off the hungry field trying to chase her down in Cincy?